Yes. To edit who is assigned to a theater seat, open Workspace>Events>Event Seating Map and select the applicable theater event. You can search for a ticket holder in the search field at the top of the page or sort and filter the columns on the list.

Once the constituent is identified, click on the edit icon on the left side of the row. You can search for a new attendee in the drop-down list or click on New Attendee in the drop-down list to create a new constituent.

Note that editing the assignment for a seat does not change the registrant who purchased the tickets. It only changes the name of the attendee.